Upcycling process for unsorted waste stream

ABSTRACT

A dynamic process for upcycling polymers. Polymers from a diverse post-consumer waste stream are gathered in a mixture. The mixture is extruded and combined with a liquid additive containing a particular PE wax at the verge of polymerization. The liquid additive is repolymerized into LDPE to form pellets. The pellets are delivered into a reactor and submerged in a suitable solvent to dissolve the LDPE. Causing a gradual and orderly separation of the remaining polymers from one another, resulting in a layered substrate. The suitable solvent, enzymes or depolymerizing compatible chemical is delivered into the reactor through independent pipes attached to tanks containing the suitable depolymerizing agent. The process repeats depolymerizing the layered substrate layer by layer with additional suitable solvents/enzymes or depolymerizing agents for each of the polymers resulting in the dissolving of the remaining polymers in an orderly manner producing a layered wax-like material for upcycling.

OTHER RELATED APPLICATIONS

The present application is a continuation of allowed and pending U.S.patent application Ser. No. 17/072,970, filed on Oct. 16, 2020, which ishereby incorporated by reference.

BACKGROUND OF THE INVENTION Field of the Invention

The present invention relates to an upcycling process, moreparticularly, to an upcycling process for plastics that can be appliedto post-consumer plastic products without the need to sort thepost-consumer plastic products by plastic type beforehand.

Description of the Related Art

Several designs for upcycling processes have been designed in the past.None of them, however, include a process that allows for a dynamicupcycling of plastics without sorting of the plastics by type throughdissolution and depolymerization.

Applicant believes that a related reference corresponds to U.S. patentpublication No. 2003/0146547 for a method for recovering mixed plasticmatter. Applicant believes that another related reference refers to U.S.Pat. No. 5,198,471 for polymer recycling by selective dissolution. Noneof these references, however, teach of a process for plastic upcyclingdone through dynamic depolymerization which eliminates the need to sortthe various and diverse plastics by type.

Other documents describing the closest subject matter provide for anumber of more or less complicated features that fail to solve theproblem in an efficient and economical way. None of these patentssuggest the novel features of the present invention.

SUMMARY OF THE INVENTION

It is one of the objects of the present invention to provide a processthat can be used for the dynamic upcycling of plastic from post-consumerplastic products.

It is another object of this invention to provide a process that canapplied to unsorted post-consumer plastic products.

It is still another object of the present invention to provide a processthat helps to reduce plastic waste and pollution.

It is also another object of the present invention to provide a processfor upcycling plastic through depolymerization.

It is yet another object of this invention to provide such a device thatis inexpensive to implement and maintain while retaining itseffectiveness.

Further objects of the invention will be brought out in the followingpart of the specification, wherein detailed description is for thepurpose of fully disclosing the invention without placing limitationsthereon.

BRIEF DESCRIPTION OF THE DRAWINGS

With the above and other related objects in view, the invention consistsin the details of construction and combination of parts as will be morefully understood from the following description, when read inconjunction with the accompanying drawings in which:

FIG. 1 represents a flowchart of the process 20 for upcycling products.

DETAILED DESCRIPTION OF THE EMBODIMENTS OF THE INVENTION

Referring now to the drawings, where the present invention is generallyreferred to with numeral 10, it can be observed that it basicallyincludes an upcycled plastic 10 achieved through a process 20.

Upcycling of polymers allows for the polymers to be reused andrepurposed in a manner that helps to reduce additional waste as isachieved with process 20. Process includes a first step 22 involvinggathering and mixing of various plastics or polymers from a diversepost-consumer waste stream to create a mixture. The plastics containedwithin the waste stream being, but not limited to: low-densitypolyethylene (LDPE), high-density polyethylene (HDPE), polyethyleneterephthalate (PET), polypropylene (PP), polystyrene (PS) and polyvinylchloride (PVC). It may be suitable to shred the mixture from first step22.

Process 20 includes a second step 24 involving processing and extrudingof the mixture of various types of plastics from first step 22 throughan extrusion screw. Second step 24 will combine the mixture with aliquid additive containing a particular polyethylene wax in canola oilas a chemical carrier. It is to be understood that the polyethylene waxis to be at the verge of polymerization. Thereby meaning that thepolyethylene wax is manufactured by dissolving LDPE into a heptane bathin a particular manner. The heptane bath is to be maintained at atemperature between 155° and 255° Celsius with the LDPE being submergedwithin the heptane bath for a period of time between 15 and 45 minutes.

The polyethylene wax may have a high molecular weight causing thepolyethylene wax to become LDPE once again when the polyethylene wax isre-polymerized through the extrusion heat after being added as a liquidadditive to the mixture. Process 20 includes a third step 26 involvingrepolymerizing of the polyethylene wax from second step 24 into LDPE orre-polymerized LDPE. During third step 26, pellets from the mixture mayform at the end of the extrusion process. Importantly, the pellets maycontain a non-homogeneous mix of various plastics along with there-polymerized LDPE from third step 26.

Process 20 further includes a fourth step 28 involving introducing thepellets from third step 26 into a reactor. Within the reactordepolymerization will occur. Fourth step 28 further includes submergingthe pellets within the reactor in heptane or another suitable solventfor the re-polymerized polyethylene wax into LDPE. The heptane is to bemaintained at a temperature between 155° and 255° Celsius. The pelletsare to be submerged in the heptane for an hour. It is to be understoodthat the heptane will be delivered into the reactor through a pipe,otherwise referred to as first arm, from a tank containing a plethora ofheptane or a suitable solvent for LDPE and HDPE. The submerging of thepellets within heptane will cause all LDPE and HDPE to dissolve.Importantly, the LDPE's solvation from second step 24, which may beaided by agitation, will cause all of the polymers or plastics that werenot dissolved by the heptane such as PET, PP, PVC, and PS to graduallyseparate from one another since they were all bonded by the sameelement, that being repolymerized polyethylene wax. The separationoccurs as the LDPE was previously serving as a molecular entanglementfactor between the polymers of the non-homogeneous mixture. Theremaining polymers will be separated based on their specific densitiesand their buoyancy in the solvent bath, the solvent bath's specificdensity will be dynamically calculated and altered using differentsuitable solvents with different specific densities, with the goal ofhaving certain plastics sinking while others floating to further pushthe polymer layered arrangement per type. Thereby resulting in a layeredsubstrate with defined compositions that may allow for the subsequentsolvation process to be possible within one same reactor, and thechemical sorting of the mixture.

The layered substrate will be in the exampling following order: PP ontop, PS underneath of PP, PVC underneath of PS and PET at the bottomunderneath of PVC. The density of PP estimated between 0.895 g/cm³ and0.923 g/cm³. The density of PS estimated at 1.051 g/cm³. The density ofPVC estimated at 1.379 g/cm³. The density of PET estimated at 1.382g/cm³.

Process 20 may include a fifth step 32 involving opening of thereactor's connection to the first arm and recovering the remainingheptane in the reactor with the first arm through distillation. Allowingfor the reactor and the layered substrate to be ready to undergo asubsequent depolymerization once again for the remaining layers ofpolymers. This means that the process will allow for the remainingpolymers to dissolve in an orderly manner.

Process 20 will continue to be applied to the layered substrate. It isto be understood that fourth step 28 and fifth step 32 may be repeatedwith different solvents to be compatible with each subsequent polymerthat is to be dissolved. Process 20 includes a sixth step 34 involvingrepeating fourth step 28 and fifth step 32. The layered substrate mayhave a top layer of PP, which is to be treated. The first arm willclose, and then a second arm attached to the reactor will open, thesecond arm may be connected to a second tank containing a second solventcompatible with PP, such as Phthalic anhydride. The layered substratewill be submerged in the second solvent for an hour at a temperatebetween 155° and 255° Celsius until the PP has dissolved, then turnedinto a wax-like material through cooling and precipitation Immediatelyafter, the reactor will be opened, and a volatilization temperature willbe applied to the reactor to extract the second solvent by phasing itout and recovering it via the second arm through distillation. Therebyresulting in the layered substrate ready to be acted on by a third armand a third solvent to dissolve an additional layer of polymer.

It is to be understood that process 20 and more specifically, sixth step34 may be repeated until every layer of polymer in the layered substratehas been treated. With each layer being treated with a different solventto dissolve the polymer of the layer next in line. Each solvent will bedelivered with a different arm attached to a different tank containingthe necessary solvent or solvents.

At the conclusion of process 20, a layered wax-like material willresult. The layered wax-like material may be used as raw material formanufacturing new plastic goods, or as a raw material for otherindustries such as the lubricant industry. Alternatively, and as theworst-case scenario, the layered wax-like material can be deposited intoa landfill. This may have better outcome than with untreated plastic, asthe layered wax-like material may have a much more compacted volume, abetter dispersing particle size and a lowered molecular weight resultingin a more benign chemical structure to the surrounding environment.

It is to be understood that any other polymers from post-consumerproducts may be combined and treated with any other appropriate solventor solvents, heat-resistant enzymes or any depolymerizing compatiblechemical, not just the aforementioned polymers or solvents. Process 20may be repeated as necessary depending on the number of layers in thelayered substrate.

The foregoing description conveys the best understanding of theobjectives and advantages of the present invention. Differentembodiments may be made of the inventive concept of this invention. Itis to be understood that all matter disclosed herein is to beinterpreted merely as illustrative, and not in a limiting sense.

What is claimed is:
 1. A process for upcycling polymers, comprising: a)gathering and mixing polymers creating a mixture; b) extruding themixture through an extrusion screw using a wax that is dispersed in aliquid carrier; c) re-polymerizing the wax in the liquid carrier into alow density polyethylene forming a combination between the mixture andthe wax repolymerized at the end of the extrusion process; d) submergingthe combination within a reactor in a suitable solvent to dissolve thewax repolymerized and separate the remaining of said polymers resultingin a layered substrate; e) opening the reactor; and f) de-polymerizingthe layered substrate layer by layer for the remaining of said polymerswith additional suitable solvents.
 2. The process of claim 1 whereinsaid wax has a molecular weight of at least 50% of the molecular weightof the low density polyethylene.
 3. The process of claim 1 wherein saidpolymers are at least one of low-density polyethylene (LDPE),high-density polyethylene (HDPE), polyethylene terephthalate (PET),polypropylene (PP), polystyrene (PS) or polyvinyl chloride (PVC).
 4. Theprocess of claim 1 wherein said mixture is shredded.
 5. The process ofclaim 1 wherein said liquid additive contains polyethylene wax inbiobased oil as a carrier.
 6. The process of claim 5 wherein saidpolyethylene wax is manufactured by dissolving a polymer in an initialsolvent.
 7. The process of claim 6 wherein said polymer is LDPE and saidinitial solvent is heptane.
 8. The process of claim 6 wherein saidpolymer is submerged in the initial solvent for a period of time between15-45 minutes, said initial solvent maintained at a temperature between155° and 255° Celsius.
 9. The process of claim 1 wherein saidcombination is in the form of pellets that remain submerged within thesuitable solvent for 1 hour per cycle, one of said polymers is treatedper cycle, the suitable solvent is maintained at a temperature between155° and 255° Celsius.
 10. The process of claim 1 wherein a combinationfor the suitable solvent is selected based on solvent density and therole of the solvent density in the density separation of the polymersbeing dissolved.
 11. The process of claim 1 wherein said polymers beingtreated need to sink within the suitable solvent and the remaining ofsaid polymers not being treated need to float in the suitable solvent.12. The process of claim 1 wherein the remaining of said polymers areseparated by density.
 13. The process of claim 1 wherein organicmaterial, metal, and glass are found in the waste stream and will alsobe separated by density.
 14. The process of claim 1 wherein saidadditional suitable solvents produce a layered wax-like material. 15.The process of claim 14 wherein said wax-like material serves as rawmaterial for manufacturing new goods.
 16. The process of claim 1 whereinsaid polymers are selected from a diverse post-consumer waste stream.17. The process of claim 1 wherein opening the reactor further includesrecovering the remaining of said suitable solvent within the reactorthrough distillation.
 18. The process of claim 1 wherein saidcombination is in the form of pellets.